The 28-year-old Munster second row will win his 22nd cap in Saturday's Guinness Series opener against South Africa at Lansdowne Road.

With Paul O'Connell and Donncha O'Callaghan entering the twilight of their careers, Ryan has the opportunity to establish himself as Ireland's foremost lock.

A man-of-the-match performance against Scotland in March points to a player at ease in the Test arena, but he will never take his position for granted.

"In my first year of rugby I made the Munster youths and the Irish youths and I started believing I was very good," he said.

"I went into St Munchin's (College) a year later. It's a very lonely place when lads think you're too big for your boots. It was a great lesson for me and I'll never forget it.

"It was more of a case of where I thought I was better than I actually was. I've no problem saying that.

"At that age when you come from a small town and you're making the dizzy heights of the Nenagh Guardian, you actually believe it when people are telling you you're great.

"I was only 17 at the time and so was very gullible. When it comes too thick and fast you start thinking you could be that good.

"But sport is the best leveller of all, especially in rugby. If a guy is getting too big for his boots you can do him. It was brilliant.

"Munchin's for me was a tough place to go. I got a good Leaving Cert, got a Senior Cup and made some good friends.

"It was a great learning experience and I wouldn't be here if I hadn't had that."

Another deflating episode was endured during the summer tour to New Zealand when Ireland were on the receiving end of a Test series whitewash.

The hope that a first triumph against the All Blacks was imminent generated by a undeserved 22-19 loss in the second match was shattered a week later during a 60-0 rout.

It was a difficult result for Ireland to stomach and Ryan admits the pain took considerable time to subside.

"One game can make or break you. The last game we played in New Zealand....there's no two ways about it that the week before we all thought we could have made it," he said.

"After that we were broken men for four weeks. There was a lot of hurt there and you bring it with you.

"If you are not clever enough to learn from those experiences, you'd be a very foolish rugby player."

Ireland name their team to face South Africa at lunchtime tomorrow.

Ryan is expected to feature in the second row alongside O'Connell, who is winning his battle with a back injury.

Ireland have yet to announce who will lead the team in the injury-enforced absence of Brian O'Driscoll and while O'Connell is favourite for the post, coach Declan Kidney could opt for Jonathan Sexton or Jamie Heaslip with one eye on the future.

Simon Zebo and Denis Hurley are competing for the full-back duties with Keith Earls replacing O'Driscoll at outside centre.